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Effective immediately we will be deleting, without notice, any negative threads or posts that deal with the use of encryption and streaming of scanner audio.

We've noticed a huge increase in rants and negative posts that revolve around agencies going to encryption due to the broadcasting of scanner audio on the internet. It's now worn out and continues to be the same recycled rants. These rants hijack the threads and derail the conversation. They no longer have a place anywhere on this forum other than in the designated threads in the Rants forum in the Tavern.

If you violate these guidelines your post will be deleted without notice and an infraction will be issued. We are not against discussion of this issue. You just need to do it in the right place. For example:
https://forums.radioreference.com/rants/224104-official-thread-live-audio-feeds-scanners-wait-encryption.html

BCD996T features and performance

Member

Over the past 10 days I've invested almost $1,200 in Uniden scanners. That would be the BCD396T and the BCD996T. This should make me a good customer. I had heard a lot of good things about the BCD996T, but then again I had also heard a lot of good things about the BCD396T.

The 996 has great features, especially multi-site systems and the ability to set analog mode or digital mode on channels. Setting digital only helps eliminate the digital buzz and decoding delay on the 996, which can be as long as 2 seconds if you keep it on All Audio mode. I hope that both of these features can be added to the BCD396T in a future firmware upgrade. I don't see why it wouldn't be possible other than flash memory size limitations or marketing/political reasons.

Now the question is, how does it work on a digital system in the middle of a city that has digital?

The answer to that is, it...oes...rk...ve...w...at...l...no...rl..........P...6.

Can't understand that? It must be because there's another transmitter 12.5kHz away from the frequency of this forum!

The reality of the new digital systems is that they really do use 12.5kHz spacing, and there very well may be another signal 12.5kHz away from the one you want to listen to. And if a radio can't handle that reasonably well, you're not going to have much luck listening to anything on those systems.

The 996, like the 396, does an excellent job of decoding a clean digital signal. But as soon as another transmission from a channel 12.5kHz away starts splattering over what you're listening to, you can forget about hearing more than every 4th or 5th word...That is if it can decode anything at all. And no, the attenuator doesn't help.

Dynamic memory, alpha tags, Close Call, GPS, hazard alerts, location keys and all that are nice features but they don't do much good if the receiver itself can't handle the realities of modern radio systems. A good receiver costs a lot of money and since these scanners are already over $500, the only choice seems to be removing some features if you build a scanner with a better receiver. Personally I vote for improving the receiver to cope with the channel spacing of modern systems before adding any more features. Heck I'd even say give me a digital scanner with the features of the BC245 and I'll pay $500 for it if it can reject adjacent-channel interference in an urban environment. That's right, no alpha tags, no dynamic memories, nothing! Just a digital scanner that works even when two adjacent frequencies are active at the same time.

Member

Yes it does. If anything the BCD396T seems worse than the BCD996T when it comes to selectivity. The Pro-96 and Pro-2096 also have some problems in this area but overall the Radio Shack models seem better at rejecting adjacent-channel interference.

The problem isn't just caused by the spacing, it only happens when two adjacent channels are active. For example, if you're trying to listen to a transmission on 857.1125 and another transmission (from the same or different system) is active nearby on 857.1250, you aren't going to be able to hear much of what you want to hear. And even worse, if you want to listen to 857.1125 and another system (or the same system) has the control channel on 857.1250, you will be affected by that interference all the time since the control channel is always transmitting. The weaker the signal you want to listen to is and the stronger the adjacent signal is, the worst the problem will be. When the BC296D first came out I thought it was a problem with CQPSK reception since the problem didn't happen on C4FM systems. But after troubleshooting it I was 99% sure that the problem was caused by the closer channel spacing of the CQPSK systems. Suburban hobbyists might never notice the problem because they would never be near the transmitting towers, but once you get "in the middle of it all" there are a lot of transmitters on adjacent frequencies and it becomes difficult if not impossible to consistently monitor the digital systems.

Uniden Representative

What specific systems and frequencies are you having difficulty monitoring? What is your monitoring location?

There are several spots on my drive to/from work where no scanner I've ever carried will work well on the surrounding 800 MHz PS systems (but the 996 has closed those gaps significantly for me). This would include the BC296D, BC796D, PRO-96, PRO-94, PRO-43, BCD396T, BCD996T, PRO-97...(yeah, I have to use all of these from time-to-time).

I have high hopes that, by moving Nextel and similar services up so that it isn't possible for them to have a 3KW channel adjacent to public safety's .3KW channel, much of this will be solved for us (as well as for public safety) by rebanding.

Member

I'm having trouble monitoring the Phoenix simulcast systems (A through E) from about 20th Street and Camelback in Phoenix. It's especially difficult to monitor the D (Mesa) system without picking up interference from the A and B systems. Of course I don't live in Mesa, but I'm obviously going to program more than just my local freqs into a 6000 channel scanner. I could make a list of the voice channels that have the most trouble, since some are worse than others, but I don't know how it would help. This is the same problem I've been dealing with since the release of the BC296D. When I got that radio, I spent a lot of time experimenting before I learned how to recognize adjacent-channel interference.

This is not to suggest that my 396 and 996 are broken or that the 396 and 996 aren't working according to specification. I understand that designing and manufacturing a radio with high selectivity costs a lot of money. It's possible that channel spacings have gotten so tight that it's impractical to design a consumer-grade scanner with sufficient selectivity to stand up to the rigors of an urban radio environment. My post was intended to discuss this problem since it's difficult to get information on this particular issue as it relates to urban scanner users. Apparently most scanner hobbyists live in the suburbs. And it was also to express my frustration that the same limitations still exist, since I had high hopes that the 396 and 996 would improve on this issue.

Member

icp957:
I had experiance the similar ajacent channel interference in Taipei. When BR330T settings is step size 12.5kHz and mode NFM, it occurs frequently between 485.0 and 490.0 MHz police band. This band is mixed AEGIS digital trunking system for Taipei , Kaohsing and analoge system for the whole Taiwan area. Therefore I hope scanner can withhold such strong digital signal from ajacent channel.

I intened to keyin those unused channel in northern Taiwan for scanning, BR330T occurs more frequently than BC246T/SC230. Although BC246 still exists few ajacent channel interferences.So I concluded that narrow coverage BC240T is better than wide band BR330T in term of selectivity. So I exchange my new BR330T for BC246T of my friend. Maybe you can give it a try!

Member

I have high hopes that, by moving Nextel and similar services up so that it isn't possible for them to have a 3KW channel adjacent to public safety's .3KW channel, much of this will be solved for us (as well as for public safety) by rebanding.

Member

Sorry didn't see the J/K, but unfourtainatly you and several others have a history of posting "questionable replies". Even if you are "just kidding" this is a good way to start problems, (like this) Maybe I jumped the gun on this one?........Maybe.